1. Field of the Invention
The present invention relates to a process and apparatus for transforming a metal material, which can be used for a metal having a high melting point exceeding 1,000xc2x0 C., particularly, such as gold, nickel and the like.
2. Description of the Related Art
At present, there are a large number of shaping processes for making complicated micro-shapes. However, most of the processes are based on the viewpoint of only the shaping, and there is almost no process in which functions of metals are integrated.
Therefore, metal jet processes has been already proposed in Japanese Patent Application Laid-open Nos.10-156524, 10-193079, 10-195676 and 10-226803, for shaping a three-dimensional functional structure by effectively utilizing the function of a metal material.
Each of the processes is intended to produce any three-dimensional structure by ejecting a molten metal in the form of dots, scanning the surface of a substrate by a computer control to describing a two-dimensional picture image, and laminating the picture image.
However, the processes proposed hitherto are those which involves guiding a molten metal into a nozzle and ejecting the molten metal present in the nozzle. Therefore, only the metal having a low melting point can be used, and many practical metals having a high melting point used as a functional material cannot be utilized.
This is because an apparatus including a nozzle must with stand a high-temperature state in order to use a material having a high melting point. In usual, the melting point of iron is 1,5350xc2x0 C., and when iron is used as a material, an apparatus withstanding the heating up to 1,5350xc2x0 C. is required. The temperature of fire generated by a lighter is approximately 9000xc2x0 C., and the temperature of fire generated by a gas oven is also equal to this temperature. When an electric oven producing a large output power is used, the entire apparatus is molten.
Accordingly, it is an object of the present invention to provide a process and apparatus for transforming a metal material, wherein a material having a high melting point can be ejected.
To achieve the above object, according to a first aspect and feature of the present invention, there is provided a process for transforming a metal material, comprising the steps of forming a metal material into a wire material, melting an end of the wire material by electrical discharge, and flying a molten sphere formed by the melting of the end by a gas flow.
With this feature, in order to form the molten sphere by the electric discharge at the end of the wire material and to fly the molten sphere by the gas flow, the molten sphere having a high temperature can be formed without contact with a primary device such as a nozzle, and the primary device such as the nozzle around the molten sphere can be cooled by the gas flow. Therefore, a material having a high melting point can be transformed.
According to a second aspect and feature of the present invention, there is provided a process for transforming a metal material, comprising the steps of disposing an electrode in the vicinity of an opening of a fine bore having a predetermined length enough to deliver a gas and a wire material, melting an end of the wire material by electric discharge provided between the wire material and the electrode in a state in which the wire material has been located to protrude out of the opening, and flying a molten sphere formed by the melting of the end by a gas flow delivered from the opening.
With the second feature, the opening is to be closed by the molten sphere formed by the electric discharge, but a drag is applied to the molten sphere by the gas flow ejected from the fine bore, whereby the molten metal can be flied. Therefore, the molten sphere having a high temperature can be formed and flied without contact with a primary device such as a nozzle, and the primary device such as the nozzle and the wire material can be cooled by the gas flow.
According to a third aspect and feature of the present invention, in addition to the second feature, the gas flow is generated around the outer periphery of the opening.
With the third feature, the direction of flying of the molten metal can be defined by the gas flow generated around the outer periphery of the fine bore, and hence, the molten metal can be guided to a target position.
According to a fourth aspect and feature of the present invention, in addition to the second feature, an electric field or a magnetic field is generated in the fine bore.
With the fourth feature, the position of the wire material in the fin e bore can be defined by the electric field or magnetic field generated in the fine bore, whereby the position of formation of the molten metal can be regularized. Therefore, the molten sphere can be guided to a target position.
According to a fifth aspect and feature of the present invention, in addition to any of the first to fourth features, the metal material used is a metal having a high melting point exceeding 1,000xc2x0 C.
With the fifth feature, a material having a high melting point can be used, and a structure can be shaped by effectively utilizing the function of a metal material having a high melting point and used practically.
According to a sixth aspect and feature of the present invention, there is provided an apparatus for transforming a metal material by a process for a metal material according to any of the first to fourth feature.
With the sixth feature, a structure can be shaped by effectively utilizing the function of a metal material having a high melting point and us ed practically.
Thus, the metal material transforming process and apparatus are applicable in various industrial fields. For example, in a one-dimensional application, a metal sphere is formed from a metal material having a high melting point such as gold and copper, whereby a soldering and a wiring can be carried out using this metal sphere. In a two-dimensional application, letters can be formed as in an ink jet printer, and pictures can be drawn in different colors by changing the type of the used metal material. In a three-dimensional application, it is possible to shape a three-dimensional structure, to make a three-dimensional electric circuit, and t o produce a three-dimensional inclined functional material.
The above and other objects, features and advantages of the invention will become apparent from the following description of the preferred embodiment taken in conjunction with the accompanying drawings.